The Brazilians came into the contest on the back of a 5-2 success over Egyptian super club Al Ahly just three days ago and the visitors from KZN were no match for them on Tuesday.
Forward Peter Shalulile shot to the top to the goal-scoring charts with a brace while a Cassius Mailula strike, an own goal by Ricardo Nascimento and a Mothobi Mvala header rounded off the scoring.
The five-time defending champions had a scare early on when the visitors went on attack only for Sedwyn George to hit the woodwork after ghosting in at the far-post.
Masadawana quickly dusted themselves off though and completely dominated the rest of the first half that saw them hit the back of the net three times.
Starlet Cassius Mailula gave the hosts the lead after 20 minutes, finishing off a lovely team move that opened up the Royal AM defence.
It was 2-0 after 27 minutes when former Sundowns defender Nascimento gave an errant back pass to his goalkeeper Xolani Ngcobo who wasn't in position and the ball hit the back of the net.
Shalulile scored his first of the game after yet another neat team move that saw the Namibian striker lash the ball into the roof of the net.
The halftime break did not stop the home team's dominance and Shalulile netted his brace just seven minutes after the interval, firing in after a ball was knocked down from a corner.
Lantshene Phalane pulled a goal back for Royal AM with 20 minutes remaining, and it was brilliantly finished as the number eight struck a fierce effort from outide the box into the top-corner that gave shot-stopper Ronwen Williams no chance.
Sundowns restored their four-goal cushion though when defender Mvala headed in from a corner after 74 minutes.
The champions then showed a glimpse into the future when 16-year-old sensation Siyabonga Mabena was introduced from the bench to replace Themba Zwane making it a very fruitful evening.